A vector network analyzer (VNA) is a reflectometer-based electronic instrument that can be used to measure the frequency response (magnitude and phase) of a device under test (DUT) such as an electrical network, component, circuit, or sub-assembly. A VNA makes use of a frequency sweeping source or stimulus, directional couplers, and one or more receivers that provide ratioed amplitude and phase information such as reflection and transmission coefficients. VNAs commonly measure scattering (S-) parameters because reflection and transmission of electrical networks are relatively easy to measure at high frequencies. S-parameters describe the electrical behavior of linear electrical networks and devices when undergoing various steady state stimuli by electrical signals. VNAs are often used to characterize two-port networks such as amplifiers and filters, but they can be used on networks with an arbitrary number of ports.